4kw solar system during winter?

[pete2007]

Hello, we just purchased a 4kw solar system and would like to know what the average wattage / amount of pound sterling this system should be producing on a winters day?

We are based in the UK, south facing roof

Thank you in advance

[Naptown]

Not enough info given in your post but you can calculate here http://gisatnrel.nrel.gov/PVWatts_Viewer/index.html

[bonaire]

That's a question you should ask your installer before the agreement is signed and they should be providing a chart of the monthly kWh production estimate based on your roof angle, location, derating of equipment, etc. You shouldn't buy a system without all your questions being answered first.

4KW roughly is going to produce about, oh, 4100-4800 kWh per year. Higher in summer, lower in winter. Let's say 300 kWh per month. Use your electric bill to figure out what 300 kWh/month is worth in terms of your local currency. That's just some guessing here but it's not too far off. In my location, 300 kwh is worth $50 USD off my electric bill at .167 USD / kWh.

[inetdog]

That's a question you should ask your installer before the agreement is signed and they should be providing a chart of the monthly kWh production estimate based on your roof angle, location, derating of equipment, etc. You shouldn't buy a system without all your questions being answered first.

4KW roughly is going to produce about, oh, 4100-4800 kWh per year. Higher in summer, lower in winter. Let's say 300 kWh per month. Use your electric bill to figure out what 300 kWh/month is worth in terms of your local currency. That's just some guessing here but it's not too far off. In my location, 300 kwh is worth $50 USD off my electric bill at .167 USD / kWh.

In the UK there are some very bizarre FIT rules which make the simple comparison of power produced to cost of the same amount of power consumed a serious underestimate. One of the, to my mind anyway, stranger variations is to pay a higher rate for audited production which is consumed locally than for audited production that is sold back to the grid.
This results in people using opportunity loads or just straight out wasting any overproduction to get a better return.
In the US most net metering plans either offset the cost of equivalent power by time of use or even favor sell-back over local use.